The invention relates to a crankcase for an internal-combustion engine, particularly for a horizontally opposed engine, according to claim 1.
From German Patent Document DE 40 01 514 A1, a two-part crankcase for a horizontally opposed engine is known, whose two halves are screwed to one another in the area of the bearing blocks for the crankshaft which are integrated in the crankcase. Since the bearing blocks with the bearing bores for receiving the crankshaft extend at the level of the cylinder bores, the bores for receiving the bearing bolts must be placed at a corresponding distance from the circumference of the cylinder bore, as illustrated in the drawing of German Patent Document DE 40 01 514 A1. This results in a corresponding distance between the bearing bore for the crankshaft and the bores for fastening the two crankcase halves, which distance, under certain circumstances may result in an undesirable gaping of the bearing blocks during the operation of the internal-combustion engine.
It is therefore an object of the invention to implement the screwed connection of the two crankcase halves such that the bearing bolts can extend close to the bearing bore for receiving the crank pins.
According to the invention, this object is achieved by means of the characteristics of claim 1.
As a result of the fact that the screwing-together of the two crankcase halves takes place diagonally, that is, at an angle with respect to the center axis of the cylinder bore, the bores for the screwed connection of the bearing blocks may extend closer to be bearing bore. So that the transverse forces occurring in the case of a diagonal screwing-together are eliminated, the plane of division of the two crankcase halves extends essentially at the same angle at which the longitudinal axis of the bearing bolts is aligned with respect to the center axis of the cylinder bores. In other words, the longitudinal axis of the bearing bolts extends essentially at a right angle with respect to the plane of division of the two crankcase halves, so that advantageously no transverse forces occur in the case of the screwed connection according to the invention.
Additional advantages and advantageous further developments of the invention are contained in the subclaims and in the description.